Preheat oven to 350 degrees F. Line a baking sheet with aluminum foil.
Rub potatoes lightly with olive oil and sprinkle with kosher salt and pepper to taste. Place on prepared baking sheet. Bake potatoes in preheated oven for 50 minutes.
While potatoes are baking, fry diced bacon in a large skillet until evenly brown. Set aside on a paper towel to drain.
When potatoes are done cooking, remove from oven and allow to cool for 10 minutes. Cut potatoes in half lengthwise and scoop the potato flesh into a large mixing bowl. Return hollowed skins to the baking sheet and bake an additional 10 minutes.
Meanwhile, add ½ cup cheese, sour cream, milk, butter, salt, pepper, 1/2 each of the crumbled bacon and green onions to the bowl with the cooked potato. Mash or mix with a hand mixer until well blended and creamy, adding more milk, butter, and seasoning to taste.
Remove skins from oven and turn oven to High Broil. Divide the potato mixture evenly between the skins, creating a mound in the middle. Divide remaining cheese between each potato half, then broil for 5 to 8 minutes until cheese is melted and crispy. Garnish with remaining bacon and green onions, or chopped chives.
Notes
Note: Potatoes can be reheated. Brush the tops with butter, wrap them with a damp paper towel and put them on a microwave-safe plate or dish. Microwave on medium heat for 2 to 3 minutes. Unwrap, stir and check if they are heated through. If not, cook them for an additional 30 seconds to 1 minute until reheated.